Rotary disk-type assembly having a wire cutting edge



p 11, 1956 E. w. KLEIN, JR 2,762,188

ROTARY DISK-TYPE ASSEMBLY HAVING A WIRE CUTTING EDGE Filed Oct. 18, 1954 ATTORNEYS United States Patent '0 ROTARY DISK-TYPE ASSElWBLY HAVING A WIRE CUTTlN G EDGE Edward W. Klein, Jr., Atlanta, Ga. Application October 18, 1954, Serial No. 462,887

4 Claims. (Cl. 56295) This invention relates to a rotary mower blade, and has as its primary object the provision of an improved blade of this character, characterized by a wire cutting edge.

A primary object of the invention is the provision of a blade comprised of a wire cutting edge, which will retain its sharpness throughout the life thereof.

A further object of the invention is to provide such a wire which may be readily replaced with a minimum of difficulty and expense, in the event of breakage thereof.

An additional object of the invention is the provision of such a device which is relatively safe in operation, since, in the event of breakage of a wire, there are no heavy pieces to be thrown about.

An additional object of the invention is the provision of a device having a relatively frangible wire blade which is adapted to break upon the catching of the users foot thereunder, for example.

A further object of the invention is the provision of a blade which, if accidentally released from its drive shaft, avoids the tendency to sail, which occurs in the commonly used flat blades.

Still another object of this invention is the provision of a device of this character which is sturdy and durable in construction, reliable, efiicient and safe in operation, and relatively inexpensive to manufacture, assemble and utilize.

Other objects will in part be obvious, and in part be pointed out as the description of the invention proceeds, and as shown in the accompanying drawing, wherein there are disclosed preferred embodiments of this inventive concept.

In the drawing:

Figure 1 is a side elevational view of one form of blade embodying features of the instant invention, shown in association with a drive shaft;

Figure 2 is a top plan view of the construction of Figure 1, certain concealed parts thereof being shown in dotted lines;

Figure 3 is an enlarged sectional view taken substantially along the line 33 of Figure l, as viewed in the direction indicated by the arrows;

Figure 4 is an enlarged sectional view taken substantially along the line 44 of Figure 1, as viewed in the direction indicated by the arrows;

Figure 5 is an enlarged sectional view taken substantially along the line 55 of Figure 1, as viewed in the direction indicated by the arrows;

Figure 6 is a side elevational view, partially broken away, of a modified form of construction; and

Figure 7 is a side elevational view of a still further modified form of the invention.

Similar reference characters refer to similar parts throughout the several views of the drawing.

Having reference now to the drawings in detail, and more particularly to Figures 1 to 5, inclusive, there is generally indicated at 10 a support or frame for the cutting edge, which may be comprised of metal, plastic, or similar material, and which has preferably a resilient characteristic. The frame 10 consists of two parallel horizontal portions 11 which are separated by a depressed portion including downwardly extending portions 12 and a bight portion 13. The outer ends of each member 11 include a depending right-angularly positioned end portion 14, of

- a length slightly in excess of the length .of the intermediate portions 12. As best shown in Figure 4, eachend portion 14 is provided with a notch 15 which extends upwardly from the bottom thereof, each notch 15 beingaligned with a corresponding notch 16 inthe associated wall 12. As best shown in Figure 2, the notches 16 are offset relative to each other, but each notch 16 is associated with its opposite notch 15 in end portion 14, in such manner that a wire 17, extending from one notch 15 through the notches 16 to the other notch 15, is offset relative to the two oppositely disposed portions 11. The wire 17 is provided at each end with a suitable knob or projection 18, which is secured thereto in any desired manner, as by means, for example, of a set screw 19, and the arrangement is such that the wire 17 is held tightly in the notches 15 by means of the knobs 18. As above stated, the frame member 10 is preferably slightly resilient, in an outward direction, and thus serves to hold wires 17 in taut relationship. When the device is rapidly rotated in a manner to be more fully described hereinafter, centrifugal action also assists in holding the wire tightly in its associated frame.

A drive shaft 20 extends through a suitable aperture in the bight 13, and is held in position as by means of upper and lower nuts 21 and 22, respectively. A pulley or disc 23 is positioned between the nut 21 and the bight 13, and is provided with a V-shaped channel or groove 24 for the reception of wire 17 as it passes across the bight 13 from one notch 16 to the other.

A modified form of construction is disclosed in Figure 6, wherein the frame comprises an elongated flat member 25 having two depending end portions 26 provided with notches 27 for the reception of the ends of a straight wire 28, the wire 28 being provided at its ends with knobs 29 similar to the knobs 18. This assembly is provided with a centrally positioned drive shaft 30 secured in position by upper and lower nuts 31 and 32.

Still another modification is disclosed in Figure 7, wherein the frame comprises a bow-shaped member 35, the ends of which are provided with notches 36 for the accommodation of the ends of a wire 37, the ends of which are provided with knobs 38, also similar to the knobs 18. A drive shaft 39 is held in position centrally of the bowshaped member as by means of upper and lower nuts 40 and 41.

The drive shafts 20, 30 and 39, respectively, are adapted to be driven by any suitable source of power carried by a conventional mower frame of any desired type.

It will be understood that the frame or support for the wire element may be tubular or of any suitable crosssection and may be mounted in either a vertical or horizontal plane.

From the foregoing, it will now be seen that there is herein provided an improved mower blade, which accomplishes all of the objects of this invention, and others, including many advantages of great practical utility and commercial importance.

As many embodiments may be made of this inventive concept, and as many modifications may be made in the embodiments hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative and not in a limiting sense.

I claim:

1. A rotary mower blade comprising an elongated cutter bar, a shaft, said bar having a central opening extending therethrough through which said shaft projects, means on said shaft engaging opposite sides of said bar for clamping said bar to said shaft, means depending from said bar at opposite ends thereof, and a wire extending between said last named means and secured thereto with the axis of said wire at right angles to the axis of said shaft whereby when said shaft is rotated said wire will rotate in a plane perpendicular to the axis of said shaft.

2. A device as claimed in claim 1 wherein said bar has a downwardly oifset central portion for securing said bar to said shaft whereby the wire extending between the ends of said bar is positioned above the bottom of said shaft.

3. A device as claimed in claim 1 wherein said bar comprises a pair of arcuate end sections joined by a downwardly offset arcuate center portion.

4. A device as claimed in claim 1 wherein said bar comprises a flat central portion, and said depending memwires therebelow.

References Cited in the file of this patent UNITED STATES PATENTS bers extend perpendicularly therefrom to support said 

